Grill or pan fry ground beef patties until no longer pink and the juices run clear.
Combine mustard and horseradish to make spread.
Toast bread slices. Spread 2 tsp. of spread on four bread slices. Top with a lettuce leaf, a beef patty, a slice of cheese, 3/4-ounce red and 3/4-ounce green apple slices and 2 tsp. almonds.
